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Questions in physics

[Done] $\begin{array}{l} \stackrel{4 o n c}{(+)} \stackrel{7 o n c}{\rightarrow} \stackrel{7}{\theta} \\ \rightarrow 4.8 N \end{array}$

[Done] Biomass generators produce electricity. They use plant-based fuels such as wood chips and corn husks. The fuel is burned to heat water and create steam. The steam causes turbines to spin. The spinning blades produce electricity. Which sequence of energy transformations is described in the passage? A. Chemical energy -> thermal energy -> mechanical energy B. Thermal energy -> chemical energy -> mechanical energy C. Chemical energy -> mechanical energy -> thermal energy D. Thermal energy -> mechanical energy -> chemical energy

[Done] You are measuring the diameter of a small steel ball using a vernier caliper. The main scale reading just before the 0 of the vernier caliper is 1.2 cm. The [tex]6^{th}[/tex] line on the vernier scale aligns perfectly with a line on the main scale. Calculate the diameter of the steel ball.

[Done] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

[Done] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

[Done] How far does a car travel in 90 seconds if it is traveling at a speed of 55 m/s? Show the appropriate equation from your textbook and show your work with units. (Chapter 2 – Pages 46-47)

[Done] The gravitational force formula is [tex]F=\frac{G m m_2}{r^2}[/tex], where [tex]F[/tex] is the force between two objects, [tex]G[/tex] is the constant gravitation, [tex]m_1[/tex] is the mass of the first object, [tex]m_2[/tex] is the mass of the second object, and [tex]r[/tex] is the distance between the objects. By rewriting the formula as [tex]r=\sqrt{\frac{G m m_2}{F}}[/tex], you can find the distance between objects. Which of the following gives the distance, [tex]r[/tex], in simplest form? A. [tex]r=\frac{\sqrt{ Gm _2 m_2}}{F}[/tex] B. [tex]r=\frac{\sqrt{G m m_2 F}}{F}[/tex] C. [tex]r=\sqrt{G m_1 m_2 F}[/tex]

[Done] For an object thrown at 45° to horizontal, the maximum height (H) and horizontal range (R) are related as: (1) R = 16H (2) R = 8H (3) R = 4H (4) R = 2H 19. A missile is fired for maximum range with an initial velocity of 20 m/s. If g = 10 m/s², the range of the missile is: (1) 40 m (2) 20 m (3) 60 m (4) 50 m 20. Velocity of a projectile in its flight: (1) Remains constant (2) First decreases, becomes zero and then increases. (3) First decreases, reaches minimum and then increases. (4) First increases, reaches maximum and then decreases. 21. At the maximum height of a projectile, the velocity and acceleration are: (1) Parallel to each other (2) Antiparallel to each other (3) Perpendicular to each other (4) Inclined to each other at 45°

[Done] The Schrödinger wave equation for the hydrogen atom is: \[\psi_{2s} = \frac{1}{4\sqrt{2\pi}} \left( \frac{1}{a_0} \right)^{3/2} \left( 2 - \frac{r_0}{a_0} \right) e^{-\frac{r_0}{2a_0}} \], where \(a_0\) is Bohr's radius. If the value of \(a_0\) is 53 pm, then what is the value of the distance of the radial node (\(r_0\) in pm) from the nucleus?

[Done] A cardboard box weighs 0.045 kg. What will be the weight of 9 such boxes?